Consider the following geometric solids.
a sphere with a ratio of surface area to volume equal to 0.08 m-1.
a right circular cylinder with a ratio of surface area to volume equal to 2.1 m-1.
what results would you expect if these two models were compared in a diffusion test?

a. the rate of diffusion would be the same for the two models.
b. the rate of diffusion would be faster for the right cylinder.
c. the rate of diffusion would be slower for the right cylinder.
d. the rate of diffusion would be faster for the sphere.

Which is the best predictor of the radioactive nature of an isotope? o the proton-to-electron ratio the neutron-to-proton ratio o the neutron-to-electron ratio the electron-to-proton ratio

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)

Ahot-air balloon takes off from the ground traveling vertically with a constant upward acceleration of magnitude g/4. after time interval δt, a crew member releases a ballast sandbag from the basket attached to the balloon. how many seconds does it take the sandbag to reach the ground? (express your answer in terms of δt)